Electrical timing arrangement



May 2, 1933. K. H, BLOMBERG ELECTRICAL TIMING ARRANGEMENT Filed April10, 1930 K #B/am berg jm eNTaQ Patented May 2, 1933 UNITED STATES"PATENT: OFFICE KNUT BLOHBERG, ,OI'. APPELVIKEN, SWEDEN, ASSIGNOR TOTELEFONAKTIE- BOLAGET L. I. ERICSSON, OI STOGKHOLH, SWEDEN, A COMPANY OFSWEDEN ELECTRICAL TIMING ARRANGEMENT.

Application fled April 10, 1980, Serial No. 448,188, and in Sweden April15, 1929.

The present invention relates to electrical timing devices such as timerelays,- time switches etc. More especially, the invention relatestosuch devices in which the timing member is constituted by a condenser incombination with a high charging resistance and a discharge devicehaving a fixed lighting voltage, by wa of example a glow lamp or a. glowtube. gaid elements may, by way of 0 example, be mutually so connectedthat, upon operation, the condenser is charged over the resistance sothat after a predetermined period the condenser voltage has attained thelighting voltage of the discharge device.

The condenser then discharges over the discharge device whereby acurrent impulse is obtained that may actuate the device to be timecontrolled.

Such timing arrangements afl'ord great advantages by their lack ofmovable parts, their recision. and their adaptability to be adusted fordiflerent lengths of time, fromfractions of a second up to severalhours, but their application has hitherto been restricted to such caseswhen the available operating voltage has exceeded the lighting voltageof the discharge device. Existing types of glow lamps and glow tubesgenerally preferred and used for said purpose arenot at resentmanufactured for lower voltages than 0 to 80 volts and, on account ofthe nature of the glow I dischar e phenomenon, a further reduction inthe ligfiting voltage appears impracticable. It has thus not beenpossible to make use of said timing arrangements at the voltages usuallyoccurring 1n the communication art, i. e. 24 to volts.

According to the/present invention 'it has been rendered possibletoope'r'ate such timing arrangements at a lower voltage than thelighting volta e of the discharge device.

According to e invention, this is brought about by that, during thecharging of the condenser over the charging resistance, one or to theoperating voltage are series connected to the former condenser so thatthe condenser voltages during'the charging-are added together wherebythe; lightingavoltage of the discharge, device may be attalned by meansof a lower operating voltage. I

The invention will now be more closely de scribed with reference to theaccompanying drawing in which Figureldiscloses a circuit diagram of anembodiment of the invent1o n, and Fig. 2 shows another embodiment 1n asimilar manner. On the drawing,

Figure -1 is a circuit diagram for a time relay in, which the operatingvoltage is less than the lighting voltageof the glow lamp but higherthan one halfthereof. G denotes the glow lamp or glow tube, C1 and C aretwo.

condensers of suitable capacity, by way of tive position, the normallyclosed contacts 1 and 2 remain closed. Over said contacts; the

condenser C is connected to the current source E, i.e. it is standingby, charged to said potential, which is lower than the lighting voltageof the lam G. Over the contact 2 the condenser O is s ort-circuited overthe resistance 1- When the relay R isenergized, upon the starting of thetiming arrangement, the normally closed contacts 1 and 2. are opened bythe relay armature and. the normally open contacts 3 closed. Theshort-circuit of thecondenser G is thus removed and more othercondensers previously charged 0 is instead connected to the currentsource E over thehigh charging resistance r and the charging of thecondenser starts. The condenserC is disconnected at the same time fromthe current source but its voltage ,decreases very slowly on account ofthe high insulating resistance of the condenser. The

' two condensers are, as shown, interconnected in such a manner that thevoltage of the condenser C continuously increasing during 'the charging,is added to the voltage of 0 When the voltage of C after the fixedperiod has attained such a value that the resulting voltage is equal tothe lighting voltage of the glow lamp the lamp is lighted and thecondensers discharge through the lamp and the series-connected relay Runtil the resulting voltage has fallen below the extinction voltage, ofthe lam when the glow disrelay R is energized.

charge ceases. By the charge im ulse the relay R is energlzed and holdsitse f,in circuit over the contact 4 and makes or breaks,

as the case may be, the circuit to be actuated .afterthe fixed period,by way of example an alarm circuit over the contact 5 or 6 respectively.v I

The relay R is ener ed so long as the When the relay R is de-energizedthe holding-circuit of B is in-- terrupted so that said relay alsobecomes Ideenergized. At the same time, C is short-' circuited over 1',over the contact 2- and connects C to the current source over thecontacts 1 and 2. The circuit arrangement is thus restored to thestarting condition.

If the energization of the relay R is of shorter duratlon than the fixedperiod,- R will, before the discharge has taken place and the relay R,has been energized, short-circuit C and charge C to full voltage inabove mentioned manner at its normally closed contacts 1 and 2. As soonas R has thus been de-energized the timing arrangement is restored tothe starting position and afterthe re-energization of R the fixed periodmust again lapse before R operates. I

' Figure 2 shows a corresponding circuit arrangeme'nt for the case thatthe voltage E is less than about one half but higher than one third ofthe lightin voltage of thelam G.

Three condensers C, and C, vare ere series-connected during the chargingwhereas two of them, i.e. C and C are previously each charged to thevoltage E.

When R is in inoperative position 05 and G, are, over the normall closedcontacts 7, 8, 9 and 10, connected in parallel to the current source Eand thus charged to the correspondingvoltage. The condenser C1" isshort-circuited over 1', over the contact 10. When R is energized saidshortcircuit is interrupted and 0 is, over the contact 11, connected tothe current source E over the charging resistance 1' for which reasonthe voltage thereof is gradually increased. Simultaneously C, and C. aredisconnected from the current source and series connected over thecontacts 12 and 13. The

three condensers are new series connected voltage with one another andthe resulting Wh is impressed upon the glow lamp the correspondinglighting voltage is attained discharge current 15 passing through therelayR so that said relay is energized in above mentioned manner. There-chargingof the condensers C and C and the short-circuiting of C, uponthe de-energization of the relay R is completely analogous to the mannerof operationdescribed in connection with Figure 1.

It is readily understood that it is possible to combine so many partvoltages that the lighting voltage of the lamp may be attained also incase of very low operating voltages.

In order to reduce the-number of condensstrong discharge impulses, ithas been found rangement may then be carried out in sucha manner thatthe condensers C and O in inoperative position, do not stand by incontinuouslyfcharged condition but, upon' the relay R operatin for ashort moment, by way of example t rough an auxiliary relay,

are connected to the currentsource before the charging of C1 begins. v

It is readily understood that the characteristic features of the presentinvention arenot restricted only to the embodiments shown in Figuresland 2. The invention is evidently completely independent of thefunction to be performed bythe timin arrangement and it may thus beapplie in many different kinds of time rela s, time switches or the likeconnected in di erent manners.

' Also in such cases when the operating voltage is comparatively high,for instance 100 volts, and per se suflicient to light commercialdischarge devices having a. low lighting voltage, it may be preferred touse a discharge device of a higher lighting volta than the availableoperating voltage for tfi: reason that the discharge impulses will bestronger, the greater is the difference between the lighting andtheextinction voltages and saiddlfl'erence increases with the voltagerating of the discharge device. Then, of course, the resent inventlonmay be advantageously app ied to attain the required lighting volt- Iclaim:

An "electrical timing arrangement com- 'ers required while maintainingsufliciently I prising a timing condenser and a plurality of auxiliarycondensers, connected in series with one another and with a dischargedevice, a charging current source having a 5 lower voltage than thelighting voltage of the discharge device, a timing resistance, and

a switch adapted, in normal position, to connect the current source inparallel with the auxiliary condensers while separating the timingcondenser from the current source and, in timing position, to connectthe current source to the timing condenser throu h the timing resistancewhile separating t e auxiliary condensers from the current source.

2. An electrical timing arrangement as claimed in claim 1 in which thetlmin condenser has a capacity difiering from t at of the auxiliarycondensers.

3. An electrical timin arrangement as claimed in claim 1 in w ich theswitch is adapted, in normal position, to short-circuit the timingcondenser.

a 4. An electrical timing arrangement comprising a timing condenser andan auxiliary 'condenser, connected in series with one another and with adischarge device, a charging current source having a lower voltage thanthe lighting voltage of the discharge w device, a timing resistance, anda switch adapted, in normal position, to connect the current source inparallel with the auxiliary condenser while separating the timingcondenser from. the current source and, in timing position, to connectthe current source to the timing condenser through the timing resistancewhile separating the auxiliary condenser from the current source.

5. An electrical timin arrangement as claimed'in claim 4 in WhlCh thetimin con denser has a capacity difi'ering from t at of the auxiliary,condenser.

6. An electrical timin arrangement as claimed in claim 4 in wfiich theswitch is adapted, in normal position, to short circuit the timingcondenser.

In testimony whereof I aflix m si ature.

KNUT HUGO BLOKIB RG.

